Thomas mccabe



(No Model.) 7

r T. MOOABE.

STAMP GANGELING DBVIGE.

No. 274,627. Patented Mar.27,1883.

UNITED STATES PATENT OFFICE.

TnOMAs MOUABE, OF OTTAWA, ONTARIO, CANADA.

STAMP-CANCELING DEViCE.

SPECIFICATION forming part of Letters Patent No. 274,627, dated March 27, 1883. Application filed May 1, 1882. (No model.)

To all whom it may concern:

Be it known that I, THOMAS MCOABE, of Ottawa, in the Province of Ontario and Dominion of Canada, have invented certain Improvements in Stamp Canceling Devices, of which the following is a specification.

My invention relates to devices or means for canceling or obliteratingstam ps by charriug or carbonizing them 5 and it consists in a stamp containing porous platinum, whichis rendered incandescent by the delivery of hydrogen gas upon it through a tube communicating with a suitable generator, as hereinafter more fully explained, the heatof the platinum beingtransinitted to the block or canceling surface, and by it to the stamp to be canceled.

- The accompanying drawing represents asectional view of my improved device, including the gas-generator. A

My invention is based upon the fact that the delivery of pure hydrogen gas upon a body of porous platinum renders the latter incandescent, and causes it to continue in that state so long as the supply of gas continues.

The precise construction of the canceling or obliterating implement is immaterial, and the same is true of the gas'generator, provided the principle above stated be retained but a convenient form for said parts is illustrated in the drawing, in which A represents the canceling or obliterating tool, B the gas-generator, and C a flexible tube connecting the two.-

The tool A consists of a handle, a, of wood, ivory, or other non-conducting material 5 or it may be of metal or like material separated from the metal thimble b byauinterveuingnon-conducting substance-such as compressed paper, wood, bone, Sac.

The thimbleb is designed to contain and support the canceling tube or block a, which will preferably be of platinum and tubular inform, though, if desired, it may be fashioned into any desired form of marking device. Within the tube or block '0, which will in every casebe hollow, is secured a ball or piece, d, of spongy or porous platinum, held in place by metal supports 0, which serve also to transmit heat from the spongy platinum to the canceling tube or block 0 by their conductivity. 7

f represents a tube,which passes through the side of the handle-piece a, and down through the same and the thimble b to a point directly over the ball or block (I to deliver gas thereon,

the outer end of the tubeprojectin gsnfiiciently to receive or permit the attachment ofthe end of the flexible tube (1, by which gas is conducted from the generator B to the implement.

The tool being thus constructed, it is simply necessary to supply gas to the tube Uand cause its delivery upon the spongy platinum, when the latter, becoming red hot or incandescent, transmits its heat to the canceling tube or block c,whioh, being applied to a stamp, chars or carbonizes the same, so that it cannot possibly be reused without detection.

The gas-generator B consists of a glass jar or other vessel, 9, an inner cylinder, It, which may also be of glass and notched or perforated at the lower end to permit the acid to flow from one to the other chamber, a cover, '5, flanged or grooved to fit the jar and cylinder, a suspension-rod, j, hanging from the cover in the cylinder h, and a basket or cup, 70, containingzinc, iron-filings, or other substance capable of givingoft' hydrogen gas when acted upon by acids.

The cover is also furnished with a central outlet tube or pipe, I, provided with a valve or cook, in, and adapted to receive the flexible tube G, as shown, and with a safety-valve, n. Being thus constructed, the safety-valve is opened and the tube G is detached and acid poured in through the tube. The safety-valve n and the cock m are then closed, the tube U is replaced, and, the generation of gas commelicing at once, the pressure of the gas forces the acid out of the cylinder It and into the surrounding space between it and the jar or vessel g, and out of contact with the metallic substance in the basket is; but as soon as the cock at is opened and the gas allowed to pass ofit through the tube 0, to be delivered upon the spongy platinum, the pressure in the cylinder h ceases, or is so diminished that the acid flows back, and, acting upon the metallic substance in the basket, the generation of gas becomes constant.

As above stated, I do not confine myself to the particular form of generator herein shown and described, though it, is found to be admirably adapted to the purpose.

The gas may be compressed and stored in receivers, if desired, and delivered therefrom to the implement.

The gas-delivery tube will be provided near the heat, or the flame, if there be any, in the herein described, but onlyits combination with 'celing or obliterating stamps, consisting in a its outer end with a bundle offine wires, wire- I gauze, or other sai'ety device, to prevent the ignition of the gas in'the tube or generator from implement, as is now done in oil stoves and lamps. V

I do not broadly claim the gas-generator the canceling device shown, being aware that a generator of quite similar construction has before been used for other purposes.

Having thus described my invention, what I claim is- 1. The herein-described apparatus for can- 2. A stamp canceling or obliterating device,

consisting of a handle, a canceling block or tube, a ball or block of spongy or porous platinum connected or in contact with the canceling-block, and an inlet-tube adapted and arranged to deliver gas upon the platinum.

3. A stamp canceling 0r obliterating device provided with a block or ball of spongy platinum, whereby it is adapted to be heated by the delivery of hydrogen gas upon the platinum.

4. In combination with a stamp canceling or obliterating device, such as described, ahydrogen-gas generator, B, consisting of vessel g, cylinder h, cover i, provided with safety-valve and. valved outlet-pipe, suspension-rod and cup or basket 70, all constructed and arranged as shown.

THOMAS MoOABE. Witnesses:

W. F. WALSH, WM. HANRIIGHT. 

